<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width,initial-scale=1,user-scalable=no">
    <title>React</title>
    <script>
        (function(){
           let num=1/window.devicePixelRatio;
           let $html=document.documentElement;
           let meta =document.createElement("meta");
           meta.name="viewport";
           meta.content="width=device-width,initial-scale="+num+",user-scalable=no";
           $html.appendChild(meta)
           $html.style.fontSize=$html.offsetWidth/10+"px";
        })()
    </script>
  </head>
  <body>
    <div id='root'></div>
  </body>
</html>
